Others have attempted to use hoses filled with water using the siphon principle to clean out the sump of a cooling tower, however, the sediment and heavy particles still remain on the bottom and insufficient negative pressure is created to properly clean the sump. Prior art has, however, used the siphon principle in conjunction with other mechanisms to accomplish a variety of tasks, some pumping by hand to fill the hose and start the siphon, others using check valves for the same purpose. Still others combine the venturi principle with a siphon to draw liquids from another source.
A search of the prior art did not disclose any patents that read directly on the claims of the instant invention, however, the following U.S. Pat. Nos. were considered related:
______________________________________ Patent No. Inventor Filing Date ______________________________________ DES 284,603 Loignon Jul. 8, 1986 DES 244,937 Houk Jul. 5, 1977 4,574,828 Brumfield Mar. 11, 1986 4,414,997 Jacobson et al Nov. 15, 1983 2,197,509 Reilly et al Apr. 16, 1940 2,131,743 Loughridge Oct. 4, 1938 ______________________________________
Loignon in U.S. Pat. No. Des. 284,603 presents a siphon fitting with a cone-like coverging throat and a side outlet interfacing at the vena contracta of the throat followed by a diverging nozzle apparently for drawing fluids into the mainstream by the siphon effect.
U.S. Pat. No. Des. 244,937 issued to Houk teaches a similar device, as above, with a side fitting entering a tube with cone-like converging section followed by a section of lesser size obviously increasing the velocity of a fluid drawn from the side fitting.
Brumfield in U.S. Pat. No. 4,574,828 has a hand operated pump and siphon having a pair of telescoping hollow tubes that reciprocate one with the other. A valve at each end holds the fluid inside and seal due to pressure differentials within. Siphoning occurs when the angle is rotated, therefore, no separate priming is necessary.
U.S. Pat. No. 4,414,991 of Jacobson et al disclose a siphon for transferring fluid using a one-way check valve on one end of a tube. The device is inserted into a container with liquid present and by shaking the tube up and down, the fluid fills the hose and flows by gravity therethrough.
Reilly et al presents a complex apparatus for separating solids from sewage in U.S. Pat. No. 2,197,509 wherein gravitational forces move the liquid from one chamber to the other with the solids collected in a hopper at the bottom.
U.S. Pat. No. 2,131,743 issued to Loughridge employs a venturi siphon using an air blast from a pump, or the like, to start the flow of fluid. Other elements are added, such as a float valve, storage tank, etc., for dispensing liquids.
In searching the prior art, no specific siphons were found that used collecting chambers with smooth walled converging nozzles to maintain and encourage entrainment of debris by increasing velocity within a tube.